Two thiazole-containing metalloligands based on the Cu(II) (P1) and Zn(II) (P2) comprising 2-(2-Pyridyl)-4-methylthiazole-5-carboxylic acid (HL1) and their extended heteroleptic metal-organic frameworks (MOFs) (CP1-CP2) have been prepared and further explored toward sensing. These compounds have been characterized through various spectro-analytical techniques, including elemental analysis, FT-IR, ESI-MS, SEM with EDX, PXRD, TGA, DSC/DTG, UV/vis and fluorescence spectroscopy. Structure of P1 has been confirmed by X-ray single crystal analysis. These compounds have been examined as chromogenic and fluorescent probes toward a series of amino acids wherein, P1 and CP1 showed highly selective chromogenic changes and fluorescence enhancement with Z-l-phenylalanine, respectively in aqueous-DMSO media. Notably, the association constant and detection limit were determined to be 2.25 × 105 M−1, 7.0 × 105 M−1 and 5.88 ppb, 0.39 ppb, respectively. Job's plot analysis, MALDI-TOF mass spectrometry and HRMS studies suggested the plausible interaction/ binding of Z-l-phenylalanine with P1 and CP1.